Beau Ryan had two words for The Footy Show fans on Thursday night: Bieber Fever.

The former West Tigers player-turned-NRL funny guy "took one for the team" when he transformed into the Canadian megastar - who is currently in Australia for his Purpose tour - as part of his regular 'Beau Knows' segment.

Kitted out in full Biebs merchandise and sporting a freshly bleached head of platinum locks, Beau told viewers he was gearing up for the biggest day of his life because "I get to witness the greatest ever Justin Bieber live".

"Today is a very, very big day and that means we need some very, very big transport," Beau said, before jumping into a Hummer or "Beau's Bieber Bus".

But before hitting the Bieber concert at ANZ Stadium, Beau explained the plan was to stop at a Sydney shoe store, where Justin, 23, was due to appear.

"We thought it'd be fitting if I turned up and created some mayhem," Beau said between busting out some moves, including some solid hip thrusts in the backseat.

As the car pulled into the shopping centre, swarms of Beliebers were sent into a frenzy as the jokester strategically wound down his window, slightly revealing his blonde spikes.

Next, he jumped out of the car and proceeded to hug fans, many of them now realising that the tall intruder was in fact, not Biebs.

His next task was to "make some friends" and pick up a group of Beliebers to attend the stadium performance with him.

They cranked 'What Do You Mean' and made their way to Homebush before Beau found some more fans to chat to, including Cronulla Sharks CEO Lyall Gorman who was hitting the concert with his daughter.

There was more dancing, more singing, and even an "ass" tap from an excited punter. Which ended up being the only take-home for Beau, who sadly lost his ticket and failed to convince organisers that he had one.

At the end of the clip, police escort him out and Beau tells us, "I guess I'll just wait for him at the hotel."